Golf balls generally comprise a resilient core that is surrounded by a cover. The core may be either a wound core or a solid core, and the cover is typically molded about the core. For example, the cover typically is either compression molded from two half shells or injection molded about the resilient core.
The covers of modern golf balls are made from a variety of materials, such as balata and ionomer resins, such as Surlyn.TM., a species of resins developed in the mid 1960's by E. I. DuPont De Nemours & Co. The balata material tends to be a softer material that provides the golfer with greater control of the golf ball, while Surlyn.TM. covers tend to be harder and less subject to nicks or cuts. Attempts have been made to develop certain hybrid covers having materials or blends that provide the feel and control afforded by a balata cover while maintaining a higher degree of durability, as with Surlyn.TM. covers.
Additionally, golf ball covers have been modified in a variety of ways by the addition of various logos or other markings. Some of these logos are simply stamped onto an exterior surface of the ball, but such logos are subject to nicking and marring during use. Attempts have also been made to locate logos or other markings within or beneath the cover. For example, golf balls have been manufactured by wrapping the core with a layer of material having desired markings and then providing a transparent Surlyn.TM. cover.
It would be advantageous to design a golf ball having a cover with different regions of unique material characteristics. For example, certain portions of the cover could be harder than others, or certain portions could be transparent while the other portions remain opaque. Such a design would provide flexibility in selection of materials to accommodate, for instance, logos disposed beneath the cover, while maintaining (over the remainder of the golf ball core) a material having optimal ball control characteristics.